Mounting bracket for electrical terminal block devices

ABSTRACT

A MOUNTING BRACKET HOLDS ONE OR MORE STANDARD ELECTRICAL TERMINAL BLOCK DEVICES FOR MOUNTING ON A WALL OR PANEL WITHOUT REQUIRING USE OF A MOUNTING OR TERMINAL STRIP. COOPERATING HANDLE LOCK-OFF MEANS MAY BE USED FOR LOCKING A TERMINAL BLOCK KNIFE SWITCH IN ITS OPEN POSITION.   D R A W I N G

United States Patent [1 1 Schurr MOUNTING BRACKET FOR ELECTRICAL TERMINAL BLOCK DEVICES [76] Inventor: C. Allan Schurr, 19805 Scottsdale,

Shaker Heights, Ohio 44122 22 Filed: May 16, 1972 21 Appl. No.: 253,753

[52] US. Cl. 248/223, 200/168 B, 317/119, 339/198 G [51] Int. Cl. II0lh 9/08 [58] Field of Search 200/168 R, 168 B, 168 C; 317/119, 118; 339/198 R, 198 N, 1980;

[56] References Cited UNITED STATES PATENTS 2,708,088 5/1955 Steinke 248/224 [4 1 v July2, 1974 2,871,284 l/1959 Wills 317/119 X 2,880,263 3/1959 Herrmann et a1 339/198 N 3,244,941 4/1966 Maynard et a1 317/1 19 3,289,049 11/1966 Middendorf 200/168 C X 3,668,591 6/1972 Kobryner 339/198 N Primary ExaminerJ. V. Truhe Assistant Examiner-Wi11iam J. Smith Attorney, Agent, or Firml-larold J. Rathbun et a1.

[5 7] 1 ABSTRACT A mounting bracket holds one or more standard e1ectrical terminal block devices for mounting on a wall or panel without requiring use of a mounting or terminal strip. Cooperating handle lock-off means may be used for looking a terminal block knife switch in its open position;

2 Claims, 8 Drawing Figures PATENTEUJUL 2 I974 SHEEY 1 0F 2 M W LT MOUNTING BRACKET FOR ELECTRICAL TERMINAL BLOCK nrtvrcla's It is well known to use terminal block devices for terminal connection of panel mounted electrical equipment. Various terminal block devices may be mounted as desired on a mounting or terminal strip which is in turn affixed to the panel. Such a terminal strip and its associated terminal blocks are disclosed in US. Pat. No. 2,981,922, issued to Hermon L. Van Valkenburg and Erik .1. Nielsen on Apr. 25, 1961, and have great versatility in that many varieties of terminal block devices can be mounted on the terminal strip. One of these is a terminal block knife switch as disclosed in my U.S. Pat. No. 3,624,333, issued on Nov. 30, 1971.

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It is often desirable to mount a one-, twoor threepole knife switch on a wall or panelboard to serve, for example, as a control circuit disconnect switch. It is generally desirable to mount such a switch separately from any terminal strip which may be used in conjunction with the equipment. One-, twoand three-pole knife switches are commercially available and generally used for this purpose. However, they are relatively expensive .and not readily interchangeable so that complete stocksrnust be maintained for each variety of switch. Also, if the switch must be fusible or capable of being locked in the open position, additional expense and stocking problems result.

The mounting bracket of this invention eliminates these and other problems by providingan inexpensive, simple and efficient means for mounting a one-, twoor three-pole knife switch, fusible or unfused, and with or without locking capabilities, through the use of a small number of parts.

it is an object of this invention to provide a mounting bracket for terminal block devices which allows a small number of terminal blocks to be securely mounted on a wall or panelboard without the use of a terminal strip.

it is another object of this invention to provide a mounting bracket which permits assembly and mounting of one-, twoand threepole knife switches without requiring stocking of a large number of expensive components.

it is a further object of this invention to provide a mounting bracket including means for adapting a one-, twoor three-pole knife switch assembled therein to be locked in the open position.

it is a still further object of this invention to provide a mounting bracket which permits assembly and mounting of knife switches which may be one-, twoor three-pole, may be fusible or unfused, and may be adapted for locking in the open position while requiring stocking of only a small inventory of relatively inexpensive components.

These and other objects and advantages of the present invention will become apparent from the following description when read in conjunction with the accompartying drawings, in which:

P16. 1 is an exploded perspective view of a plurality of terminal blocks with a mounting bracket and knife switch locking means in accordance with this inven- FIG. 2 is a fragmentary side view of a terminal block andamounting bracket illustrating assembly thereof;

FIG. 3 is a fragmentary cross sectional view taken generally along the line 3-3 of H6. 2;

FIG. 4 is a cross sectional view similar to FIG. 3 of a multi-pole mounting bracket holding a plurality of terminal blocks; 7 FIG. 5 is a perspective view of a single-pole knife switch assembly in accordance with this invention and shown in its open position;

FIG. 6 is an end view of a three-pole knife switch assembly in accordancewith this invention;

FIG. 7 is a plan view of a punched blank which may be bent to form a single-pole mounting bracket in accordance with this invention; and

FIG. is an end view of the single-pole knife switch of FIG. 5 shown in its closed position.

Referring now to the drawings, FIG. 1 illustrates a three-pole mounting bracket 11, in accordance with this invention, adapted for holding a plurality of terminal block devices. The terminal block devices may be of various types, such as a fusible terminal block device 12f illustrated in detail in U.S. Pat. No. 3,302,160, issued on Jan. 31, 1967, to Erik J. Nielsen, and a terminal block knifeswitch 12k, as disclosed in my aboveidentified U.S. Pat. No. 3,624,333.

Both the fusible terminal block device 12f and the terminal block knife switch 12k are formed by assembling appropriate components in a standard terminal block 14. The terminal block 14 is described in the above-mentioned U.S. Pat. No. 3,302,160 and is preferably constructed of a molded phenolic material. Each terminal block 14 is generally L-shaped and has a pair of horizontally elongated, generally rectangular projections 15 (FIG. 3) formed in .one side thereof and a pair of recesses (not shown) shaped and positioned to at opposite sides of the terminal block devices to facilitate mounting in the bracket 11, as will be subsequently explained.

Each mounting bracket, either in the form of a threepole mounting bracket 11 or a single-pole mounting bracket 111, is preferably stamped from a piece of sheet metal such as illustrated in FlG. 7 for a singlepole mounting bracket 111. The single-pole mounting bracket 111 has a base or bight portion 119 and a pair of side walls 120 which extend in a direction generally perpendicular to the bight portion 119 when the mounting bracket is bent at the fold lines indicated at 121. Each side wall 120 has a projection holding slot 122 formed therein; Each slot 122 has an enlarged end portion 122a and a narrow end portion 122b to accommodate mounting of the terminal block device 12 in a manner to be described. Entrance channelsare provided in each side wall 120, each channel being defined by a pair of end tabs 124 and positioned outwardly of its respective slot 122. An outwardly directled locking tab 125 is positioned inwardly of each slot 122.

The bight portion 119 includes means for mounting the mounting bracket 111 on a wall or panelboard The three-pole mounting bracket 11 best illustrated in FIG. 1, has a pair of side walls 20 substantially identical in form to the side walls of thesingle-pole mounting bracket 111. The three-pole mounting bracket 11 differs generally from the single-pole mounting bracket 111 in only two respects. First, the bight portion 19, corresponding to the bight portion 119 of the singlepole bracket 111, is of a width to accommodate mounting of three terminal blocks 14 and an end barrier 16. Second, the bight portion 19 accommodates mounting of cooperating handle lock-off means through an opening 29, similar in configuration to the opening 129 of the single-pole mounting bracket 111, but including a holding tab 30 which, as can be seen in FIG. 4, is parallel to and offset from the plane of the bight portion 19. It should be noted that although only a single-pole mounting bracket 111 and a three-pole mounting bracket 11 have been described herein, mounting brackets for holding other quantities of terminal block devices may be made without deviating from the spirit and scope of this invention.

The cooperating handle lock-off means of this invention preferably comprises a fixed handle lock-off member 31 (FIG. 1) and a movable handle lock-off member The cooperating handle lock-off means functions to lock a knife switch, such as the switch 12k, in its open position. The knife switch 12k, fully described in my above-mentioned US. Pat. No. 3,624,333, is constructed by mounting a pivot receptacle 34 and a contact receptacle 35,'each of which includes a terminal portion, on a terminal block 14. A switch blade 36 is pivotally attached at one end to the pivot receptacle 34 and has an electrically insulating handle 37 attached at a free end portion. The handle 37 may be used to move the switch blade 36 between its open position, as illustrated in FIG. 1, nd its closed position, wherein the switch blade 36 is moved into electrical contact with the contact receptacle 35.

A terminal block device 12, such as a terminal block knife switch 12k, canbe assembled with an end barrier 16 to form a unit, as illustrated in FIGS. and 8, having the pairs of projections and 17 on opposite sides thereof. The combined terminal block and end barrier are mounted on the single-pole mounting bracket 111, as best shown in FIG. 2, by inserting one of each pair of projections 15 and 17 through its respective entrance channel between the end tabs 124 and into the enlarged end portion 122a of the projection holding slot 122 to the position shown by phantom lines in FIG. 2. The terminal block end-barrier assembly is then rotated in the direction of an arrow 39 in FIG. 2 to place both members of each pair of projections 15 and 17 in alignment with the projection holding slot 122. Moving the terminal block and end barrier in the direction of the arrow 40a to the position shown by solid lines in FIG. 2 prevents removal of the projections 15 and 17 from the respective projection holding slots 122. The locking tabs 125 may then be bent inwardly, to the position shown in FIG. 3, into respective grooves 40 formed in the terminal block 14 and end barrier 16, respectively, to lock the assembly in the mounting bracket 111.

Wot" three tarnish block dEvicTT in a three-pole mounting bracket 11 is accomplished in the same manner described with respect to the single-pole device of FIG. 2. When locking tabs 25, corresponding to the locking tabs 125 of the single-pole mounting bracket 111, are bent inwardly to hold the assembly in place, a configuration such as that illustrated in FIG. 4 is produced.

If it is desired to provide means for locking a terminal block knife switch 12k in its open position, the cooperating handle lock-off means illustrated in FIG. 1 is used. The movable handle lock-off member 32 is preferably formed of metal and comprises a handle attachment portion 41 and a lock-off portion 42, disposed generally parallel to each other and connected by a spacer portion 44. The handle attachment portion 41 is preferably shaped to fit a corresponding recess 45 formed in the handle 37 of the terminal block knife switch 12k. Corresponding openings 46 and 47 in the handle attachment portion 41 and handle 37, respectively, facilitate attachment of the movable handle lock-off member 32 to the handle 37 by suitable attachment means such as a machine screw 49 and nut 50.

The fixed handle lock-off member 31 is preferably formed of metal and comprises a base portion 51 and an upstanding lockoff arm 52. When the knife switch 12k is in its open position, the lock-off arm 52 is preferably positioned adjacent the lock-off portion 42 of the movable handle lock-off member 32, as can be best seen in FIG. 5. One or more lock-receiving openings 54 in the lock-off arm 52 of the fixed handle lock-off member 31 align with a matching set of lock-receiving openings 55 in the lock-off portion 42 of the movable lock-off member 32. A padlock or other device (not shown) may be inserted through any aligned pair of lock-receiving openings 54-55 to secure the handle 37 and switch blade 36 against motion, thereby locking the terminal block knife switch 12k in its open position.

The base portion 51 of the fixed handle lock-off member 31 is of a shape and size to cooperate with the opening 29 of the three-pole mounting bracket 11 and the opening 129 of the single-pole mounting bracket 111 for securement of the fixed handle lock-off member 31 without the use of external mounting means. The opening 29 in the three-pole mounting bracket 11 has a projection 29p formed therein corresponding in size, shape and location to a recess 5lr formed in the base portion 51 of the fixed handle lock-off member 31. Interaction of the. projection 29p and recess 5Ir mevent ateralmqtem ntqf hqfixs h ssle? s member 31. The holding tab 30 extends over an extended end portion of the base portion 51 (see also FIG. 4) and cooperates with an edge 56 of the opening 29 to hold the base portion 51 in place against the mounting surface.

Referring now to FIGS. 3 and 7, when the side walls of the single-pole mounting bracket 1 11 are folded along the fold lines 121, as previously described, a projection 129p is formed having a shape, size and position substantially the same as that of the projection 29p of the three-pole mounting bracket 11 so that the same fixed handle lock-off member 31 may be used with either the three-pole mounting bracket 11 or the singlepole mounting bracket 11].

The recess Slr interacts with the projection 129p to hold the base portion 51 against lateral motion. The base portion 51 is held against the mounting surface by an edge 156 and an edge 157 of the opening 129. The opening 129 is so shaped that the edges 156 and 157 are positioned outside the fold lines 121 as part of the respective side walls 120 so that, when the mounting bracket 111. is bent at the fold lines 121, the edges 156 and 157 are disposed in positions spaced above the plane of the mounting surface by a distance approximately equal to the thickness of the base portion 51 of the fixed handle lock-off member 31. The same relationship exists with respect to the edge 56 of the opening 29 in the three-pole mounting bracket 11. in this manner, the fixed handle lock-off member 31 may be mounted and held in place solely by the mounting bracket with both the base portion 51 of the fixed handle lock-off member 31 and the bight portions 19 and 119 of the mounting bracket 11 or 111, respectively, flush against the mounting surface. 1

One-, two and three-pole knife switches, constructed in accordance with this invention, will now be described. FIGS. 5 and 8 illustrate a single-pole knife switch assembly 59 which is assembled by mounting a terminal block knife switch 12k and an end barrier 16 in a single-pole mounting bracket 111 in the manner previously described with reference to FIG. 2. The single-pole knife switch assembly 59 may be mounted a on any suitable mounting surface by the use of mounting'screws through the keyhole aperture 126 and the slot 127 in the bight portion 119 of the mounting bracket 111.

If the cooperating handle lock-off means is required, the movable'handle lock-off member 32 may be affixed to the handle 37 of the terminal block knife switch 12k and the fixed handle lock-off member 31 positioned with its base between the mounting bracket 11] and the mounting surface to be lcpcked in place upon tightening of the mounting screws.

FIG. 6 illustrates'a three-pole knife switch assembly 60 which comprises three terminal block knife switches, such as the switches 12k, and an end barrier 16 placed side by side and mounted on the mounting bracket 11 as described with reference to FIGS. 2 and 4. The handles 37 of the terminal block knife switches 12k are joined by passing a fastener, such as a machine traw.s1 rqqshshgpnenisss 47, in t s handle .37

(see FIG. and through openings provided in spacers 62 positioned between adjacent pairs of handles 37. A

nut 50 is threaded onto the machine screw 61 to lock mounted behind the mounting bracket 11 as previously described and the movable handle lock-off member 32 may be held in place by the machine screw 61.

It should be apparent from the foregoing description that a two-pole knife switch assembly (not shown) may be formed by assembling two terminal block knife switches 12k with an empty terminal block 14 therebetween. The three terminal blocks 14, along with an end barrier 16, are mounted on the three-pole mounting bracket 11 as previously described. The handles 37 may then be joined by a machine screw 61 and nut passed through the handles 37 and an appropriate spacer. If it is desirable to construct a fusible switch having one, two or three poles, a second mounting bracket 11 or 111 may be mounted in alignment with the knife switch assembly. This mounting bracket should hold a quantity of fusible terminal blocks 12f equal to the number of poles of the knife switch assembly. The fusible knife switch assembly is then formed by electrically connecting a terminal of each terminal block knife switch 12k to a corresponding terminal of each fusible terminal block 12f.

I claim:

1. A mounting bracket for a terminal block device having projection means on opposite sides thereof, said mounting bracket comprising a base, a pair of generally parallel side walls extending in one direction from said base, each of said side walls having projection receiving means formed therein, said projection receiving means including an entrance channel permitting insertion of an end portion of said projection means into said projection receiving means, an enlarged portion permitting rotation of said terminal block device for insertion of an other end portion of said projection means into said projection receiving means, means holding the other end portion of said projection means against rotation when said terminal block is in an operating position away from said enlarged portion, and locking means for securing said terminal block device in said operating position,

2. A mounting bracket as in claim 1 wherein said terminal block device includes a groove and saidlocking means comprises a locking tab having an extended end portion movable into said groove for securing said terminal block device in said operating position.

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